Cyanamid-producing apparatus.



Patented Apr. 21, 1914.

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mats in. WEAVER, or HARRISBURG, PENNSYLVANIA.

GYANAMID-PRODUCING APPARATUS.

Specification of Letters Patent.

Application filed June 9, 1913'. Serial No. 772,600.

To all whom 1' 1% may concern:

Be it known that I, VICTOR M. l/VEAVER, a citizen of the United States,residing at Harrislmrg, in the county of Dauphin and State ofPennsylvania, have invented certain new and useful Improvements inGyanamid-Producing Apparatus; and I do hereby declare -the following tobe a full, clear, and exact description of the invention, such as willenable others skilled in the art to which it appertains to make and usethe same. 1

My invention relates to apparatus for treating calcium carbid to producecalcium 'cyanamid, and has amol g its objects that of simplifying themeans employed, as compared with those at present in use for likepurposes; of rendering the operation practically automatic, continuousand economical; of obtaining increased efficiency by avoiding theinterruptions and uneven temperatures incident to the ordinary use ofretorts and ovens heretofore employed for like purposes, wherein it hasbeen customary to introduce measured charges of calciumcarbidintermittently, with a consequent delay between reactions, andwherein such reactions were necessarily slow because of the timerequired to thoroughly permeate a latent body of calcium carbid with thenecessary amount of nitrogen gas to insure the proper chemical actionand produce the desired calcium cyanamid.

With these and other objects in view the present invention consists incertain novel features of construction and combinations of parts whichwill be hereinafter particularly described and pointed out in the claimsfollowing.

In the accompanying drawings which form part of this application forLetters Patent, and whereon like characters indi- .catecorrespondingparts in the several views: Figure 1 is a side elevation of my inventionwith one side-wall of the furnace removed, the carbid hopper being insection, and the gas tight bells at opposite ends of the apparatus beingshown diagrammatically, and, Fig. 2 is a plan view of the invention withthe furnace crown or dome removed upon Peference being had to thedrawings and numerals thereon, 1 indicates a gas ti ht cyanamidproducing oven or furnace pre erably made of fire-brick, its roof andsides being reinforced by an exterior jacket or front, is a sheet ironopening the section line 2 -2 of Fig. 1.

'nected to the outlet 17 at inner end covering 2 of sheet iron adaptedto retain nitrogen gas under pressure of about two atmospheres more orless. The roof of furnace 1 is .referably crowned as shown b Fig. 1 of te drawings, and is provided wit pipes 3 for the circulation of water asmay be required, in order that an even temperature of approximately I000centigrade more or less may be maintained'within the furnace. At itsfront, furnace 1 is provided with a horizontal feed opening 4 extendingpractically across the width of furnace, and immediately above, boltedto the furnace hopper 5 for calcium carbid having a constricted throat 6adjacent to feed opening 4, a gas tight bell 7 above for preventingescape of gas, and a feed-plunger casing latter is reciprocally mounteda feed plunger 9 conforming in shape to its casing 8, and rcciprocatedby a pitman 10 extending through the end of said casing, in turnactuated by an eccentric drive whcel'11, driven by any suitable power.In addition to bolts 12 by which said hopper 5 and easing 8 are securedto furnace 1, supports such as uprights 13, 13 may be provided, asshown.

Connected and projecting through the furnace feed- 4 well into thefurnace as shown, is a sloping heating plate 14 preferably of cast iron,provided with a gas heating pipe 15 embedded therein in convolutearrangement as best shown by dotted lines in Fig. 2, having an inlet 16at its outer end and an outlet 1 at its inner end for purposes whichwill later appear; or if desired the gas passage in said plate 14 maycomprise merely a continuous connected series of perforations orpassages having an inlet and outlet at opposite ends as stated.

Extending outward from the top of furnace 1 is a nitrogen gas pipe 18which encircles hopper 5 spirally and connects directly with inlet 16 ofthe gas heating pipe 15 embedded as aforesaid in plate 14, but obviouslythis connection between the interior of furnace 1 and pipe 15 may bevariously made, more or less directly; before entering plate 14,however, the pipe 18 should be provided with a controlling valve 19, andshould be intersected by a lateral 20, also valve controlled as at 21,for furnishing a fresh supply of purified nitrogen gas from any suitablesource (not shown). fCoir:-

o t e Patented Apr. 21, 1914.

8 below within which to the lower edge of easing 8 circulating pipe 15,is a depending pipe 22 leading to a blower 23 situated in a blowercompartment 24, and thence through a partition wall 25 into nitrogenchamber 26.

Immediately beneath the heating plate 14 at top of blower compartment 24is situated a gas or other heater 27, provided with a supply pipe 28communicating with any suitable source of gas or liquid fuel supply, forraising and maintaining plate 14 at the required degree of temperature.Projecting upward from the top of partition wall 25, and likewise fromthe top of a lower end wall 29 both crossing the furnace transversely,are a double series of guiding studs 30, between which are locatedadjacent sections of reversely reciprocating grate bars 31 eachperforated as at 32, and like plate 14 sloping downwardly at a likeangle of inclination. At their upper ends these grate bars 31areconnected by short pitman rods 33 to a multiple crank shaft 34 which isrotated continuously in one direction by any suitable power, therebyimparting to adjacent bars 31 a continuous'and alternate reciprocallongitudinal motion.

In rear of the end wall 29, between it and the back wall 35 of thefurnace proper, is provided a drop chute 36, within which is located adamper 37 having an exposed operating lever 38, and a suitable gas bell39 of any well known construction, adapted to be closed alternatelywhile removing the finished product from the furnace through the arch 40provided in said back wall. The sides of furnace 1 are furthermoreprovided with mica-covered observation holes 41 as shown, and in orderto guard against the escape of carbidbetween the furnace side walls andends of the heating plate 14', these spaces may be spanned by outwardlyflaring guard lates of sheet metal 42, as shown, or equiva ent means.

The uses and operation of my invention are substantially as follows: Byagency of heater 27 plate 14 is heated to the proper degree oftemperature, a supply of powdered calcium carbid (0210,) beingintroduced into hopper 5 through the gas tight bell or trap 7, isfedthrough throat 6 and furnace mouth 4 distributing itself, more or lessuniformly, over the sloping surface of plate 14 as indicated by Fig. 1.Plunger 9 now brought into action serves to continuously stoke or feedthe carbid, step by step, over the plate 14 aforesaid, and onto thesloping and constantly reciprocating grate bars 31 as also shown byFig. 1. Commercially pure nitro gen gas now introduced through supplypipe 20 circulates through pipe 15 and is conducted through pipe 22 toblower 23 by which it is forced into the nitrogen chamber 26 underpressure, thence upward through perforations 32 and the relatively thinlayer of carbid in a state of constant agitation above where thenitrogen reacts with the carbid to form the desired calcium cyanamid(CaNCN). This reaction or combustion of carbid and nitrogen also givesoff heat to such an extent that the necessary temperature for acontinuous reaction is maintained with little or no further assistancefrom heater 27, although it is very important to keep the temperature ofthe heating zone of the furnace between certain well understood limits,this being greatly facilitated by agency of the cooling jackethereinbefore mentioned comprising the circulating water pipes 3 embeddedin the furnace cover or roof, also by regulating the speed with whichcarbid is stoked or fed continuously onto the grate bars 31, and thereagitated, thus bringing the nitrogen into intimate contact with allparticles of the carbid in its passage. This agitation of the carbid inaddition serves the useful purpose of presenting all surfaces of thecarbid particles to action of the uprising nitrogen gas, and breaks uclinkers which might otherwise be forme The furnace is thus constantlycharged with a nitrogen atmosphere under slight pressure, the uprisingexcess gas finding exit through pipe 18 past its controlling valve 19,and back into circulation as before, a suitable amount of fresh nitrogenbeing, of course, constantly admitted by way of the supply pipe 20, andmingled with the hot gas drawn from top of the furnace as aforesaid. Thefinished, roduct after traversing the length of grate bars 31 isdischarged into the down chute 36 where it may be trapped at intervalsby closing damper 37, and removed by opening the gas bell 39 ready forcommercial uses.

I have now shown and described the best form of my improved cyanamidproducing apparatus at present known to me, but obviously variouschanges in the construction and arrangement of parts hereinbefore setforth may be madeand substituted without materially altering theoperation or departing from the spirit of my invention, and to suchequivalents I herein lay claim.

Having thus described my improvements what I new claim is.

1. In a cyanamid producing apparatus the combination in a heating zone,of grate bars within said zone adaptedto be constantly agitated, aheating plate adjacent to said bars having a therein, means orcontinuously feeding calcium carbid over said plate and grate bars, andmeans for continuously forcing a supply of nitrogengas through said barsand body of calcium carbid.

fgas heating pipe embedded j 2. In a cyanamid producing ap aratus thecombination in a heating zone, 0 grate bars within said zone adapted tobe constantly agitated, a heating plate adjacent to said bars having agas heating pipe embedded therein, a burner beneath said plate, meansfor continuously feeding calcium carbid over said plate and grate bars,and means for continuously forcing a supply of nitrogen gas through saidbars and body of calcium carbid.

3. In acyanamid producing apparatus the combination in a heating zone,of downwardly sloping grate bars within said zone adapted to beconstantly agitated, a downwardly sloping heating plate adjacent to saidbars having a gas heating pipe embed ded therein; means for continuouslyfeeding calcium carbid over said plate and grate bars, and means forcontinuously forcing a supply of nitrogen gas through said gas heatingpipe, grate bars and body of calcium carbid.

4. In a cyanamid producing apparatus the combination in a gas tightheating zone, of grate bars within said zone arranged and adapted to beconstantly agitated, a heating plate adjacent to said bars, a gas pipeleading from the interior of said heating zone through said heatingplate and beneath the grate barsaforesaid, means for continuouslyfeeding calcium carbid over said plate and grate bars, and means forcontinuously forcing a supply of nitrogen gas through said bars and bodyof calcium carbid thereon.

5. In a cyanamid producing apparatus the combination in a gas tightheating zone, of perforated grate bars within said zone arranged andadapted to be constantly agitated, a heatin plate adjacent to said bars,a gas pipe lea ing from the interior of said heating zone circuitouslythrough said heating plate and beneath the grate bars, a fresh nitrogensupply pipe communicating with the gas pipe aforesaid, means forcontinuously feeding calcium carbid over said plate and grate bars, anda blower for continuously forcing a supply of nitrogen gas through theperforations of said grate bars and body of calcium carbid thereon.

6. In a cyanamid producing apparatus the combination in a heating zone,of parallel grate bars within said zone, a heating plate adjacent tosaid bars having a gas heating pipe embedded therein, a power" drivenmultiple crank shaft for constantly agitating adjacent grate bars inreverse direct-ions, means for continuously feeding calcium carbid oversaid bars, and means for continuously forcing a supply of nitrogen gasthrough said bars and body of calcium carbid thereon.

7. In a cyanamid producing apparatus the combination in a heatingfurnace, of grate bars within said furnace arranged and adapted to beconstantly agitated, a heat storing and radiating plate projecting intothe furnace through its mouth and having a gas heating coil embeddedtherein, a calcium carbid hopper at the mouth of the furnace, a stokerfor continuously feeding calcium carbid over said plate and grate bars,and means for continuously forcing a supply of nitrogen gas through saidbars and body of calcium carbid thereon from beneath.

8. In a cyanamid producin apparatus the combination ina gas tightheating fur nace, of downward sloping grate bars within said furnacearranged and adapted to be constantly agitated by mechanical means, aheat storing and radiating plate projecting into the furnace over theupper end of said grate bars having a gas heating pipe embedded therein,a calcium carbid hop-per at the mouth of the furnace, a power drivenreciprocating plunger for continuously feeding calcium carbid from saidhopper to and over said grate bars, means for continuously forcing asupply of nitrogen gas through said as heating grate bars and calciumcarbid t ereon, a chute at the discharge end of the apparatus forreceiving the finished product, and gas tight closures for oppositeextremities of the apparatus, substantially as described.

In testimony whereof I aflix my signature, in presence of thesubscribing witnesses.

VICTOR M. WEAVER. Witnesses:

J. L. STEWART, EDWARD M. WINTERS, FREDERICK M. On.

